Currently No version of IE supports vmax units. However it can be easily emulated using calc(). Here's the reasoning.
The viewport has 2 dimensions, width and height. One of the values must equal vmin and the other must equal vmax. Consider this formula:
(vmax + vmin) = (vw + vh)
So if we solve for vmax:
vmax = (vw + vh) - vmin
So our calc() turns into
calc(<scalar> * (1vw + 1vh - 1vmin))
where Scalar is the scaling value (the number you'd normally put before vmax in your property). So if you want to write 10vmax, then scalar is 10;
Here's the method in action:
If you view the pen in IE you wont see the red square since it uses VMAX units.